Feeding sunflower meal with pullets and laying hens even at a 30% inclusion rate does not impair the ileal digestibility of most amino acids.

The use of locally available protein sources in poultry nutrition is challenging for feed manufacturers and farmers. Sunflower meal (SFM) is available in high quantities in several European countries and could be used as a poultry feedstuff at higher inclusion rates. However, its maximum inclusion rate in the diets of different poultry species and age categories is unknown. Pullets and laying hens can probably tolerate higher amounts of SFM, but only limited information is available on these poultry groups. Therefore, a digestibility trial was carried out with 8-week-old layer type pullets and 50-week-old laying hens. Beside a basal diet, SFM was fed at 10, 20 and 30% inclusion rates. Feeding SFM significantly improved the digestibility of essential amino acids (AA) of threonine, valine, lysine, tyrosine, glycine, aspartic acid, and arginine in the pullet diets. No such improvement was found in laying hens. Only the absorption of the two branch-chain AAs, leucin (pullets) and isoleucine (hens), declined due to SFM. The AA digestibility of the SFM itself was also calculated by linear regression. The coefficients were, in all cases, higher in hens than in pullets. Comparing the measured digestibility coefficients of SFM with table values, it can be concluded that high variance exists because of the differences in the methodology and the test animals in the digestibility trials. From the present trial, it can be concluded that SFM can entirely replace extracted soybean meal in pullet and layer diets, without negative effects on the protein digestion of birds.

Diet Composition and Using Probiotics or Symbiotics Can Modify the Urinary and Faecal Nitrogen Ratio of Broiler Chicken's Excreta and Also the Dynamics of In Vitro Ammonia Emission.

The objective of this research was to determine whether diet composition, or adding probiotic or symbiotic feed additives to broiler diets can modify the N composition of the excreta and the dynamics of ammonia volatilization from the manure. A total of 574 one-day-old Ross 308 broiler chickens were fed four different diets. The treatments included a corn and soybean meal-based control diets (C), wheat-based and wheat bran containing diets (W), a multi-strain probiotic treatment (Broilact®; Br), and a symbiotic additive containing Bacillus subtilis, inulin, and Saccharomices cerevisiae (Sy). Feeding the wheat-based diet significantly improved the weight gain and FCR of chickens. Treatment W also significantly increased the dry matter content of the excreta compared with the probiotic and symbiotic treatments. Both Br and Sy tended to decrease the amount of excreted uric acid, which is the main substrate of ammonia. Treatment Sy reduced the urinary N ratio of the excreta in comparison with treatment W. The symbiotic additive resulted in significantly higher ammonia emission in the first two hours. On the other hand, the dynamics of the emission was slow at the beginning and increased steeply after 15 h when the wheat-based diets were fed. Based on our results, the wheat-based diets, containing soluble arabinoxylans, and the symbiotic treatments of broiler diets have an impact on the urinary and faecal nitrogen composition of the excreta, and also on the dynamics of ammonia release from the manure.

Effect of feeding different oils on plasma corticosterone in broiler chickens.

A study was conducted to examine the effects of different oils on the plasma corticosterone concentrations of broiler chickens fed ad libitum or deprived of feed for 24 hours. A total of 36 Ross broilers were randomly assigned to one of three dietary treatments at 10 days of age and fed a grower diet supplemented with 60 g/kg soybean oil (rich in linoleic acid, C18:2n-6), linseed oil (rich in a-linolenic acid, C18:3n-3) or fish oil (rich in C14:0, C16:0, C16:1n-7, C20:1n-9; eicosapentaenoic acid and docosahexaenoic acid, EPA, C20:5n-3 and DHA, C22:6n-3), respectively, for 18 days. Dietary supplementation of fish oil resulted in lower (P < 0.05) baseline plasma corticosterone levels of chickens fed ad libitum for 18 days compared to soybean and linseed oil supplementations. Feed deprivation for 24 h induced a significant (P < 0.05) increase in corticosterone concentration in every treatment group compared to the ad libitum-fed birds. The hormone levels of feed-deprived birds did not differ significantly among groups fed diets supplemented with different oils.